In U.S. Pat. No. 3,778,114 a pneumatic outlet is disclosed having a control valve which is movable between open and closed positions relative to a discharge opening in the outlet by operating handles located at opposite ends of the outlet.
U.S. Pat. No. 3,701,460 discloses a bail assembly including a locking lever for this outlet in which a sample of the lading may be taken from one end of the outlet by removing the bail from one end only of the outlet. The end cap and bail arrangement disclosed in U.S. Pat. No. 3,701,460 is disadvantageous for the following reasons. It is expensive and difficult to manufacture. Because of dimensional tolerances in the end cap and bail assembly it is difficult to actuate the bail members and obtain proper clamping force within the locking lever to secure the end caps. In some instances when the bail is in stored position it will interfere with the rotation of the control valve. There are points on the bail arrangement where the operator can pinch his fingers and/or crack his knuckles. Furthermore, the bail is heavy and adds to the weight of the outlet. Because of these disadvantages, injuries occur to operators, and end caps are often not properly installed when cars are shipped, leading to end cap breakage in transit.
U.S. Pat. No. 4,163,583 granted Aug. 7, 1979, discloses an end cap arrangement in which large headed bolts connected to vertically extending "J"-shaped locking members maintain the end caps in closed position. The "J"-shaped locking members maintain locking handles attached to a pair of control valves in the outlet in the closed position.
In U.S. Pat. No. 4,151,935, a technique is disclosed for taking a sample of the lading utilizing the large headed bolts and "J"-shaped locking members described in Ser. No. 844,666 by spacing the "J"-shaped locking members from the operating handle at opposite ends of the outlet a distance sufficient to allow rotation of the operating handle from the near end of the outlet a distance sufficient to take a sample before the "J"-shaped locking members on the opposite end of the outlet are abutted.